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Can someone clarify me the difference (or similarity) between data and message described under Cipher Suite in Wikipedia

The key exchange algorithm is used to exchange a key between two devices. This key is used to encrypt and decrypt the messages being sent between two machines. The bulk encryption algorithm is used to encrypt the data being sent.

Sreejith Nair
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    They're the same. The messages are the data. – S.L. Barth Jan 05 '18 at 13:02
  • symmetric keys are used to encrypt/decrypt data. If so, does symmetric and bulk encryption algorithm are the same? – Sreejith Nair Jan 05 '18 at 13:41
  • Yes. Symmetric ciphers are much faster than asymmetric ciphers. If asymmetric ciphers were faster, we'd simply use them for all the data exchange. But they aren't, so the asymmetric ciphers are used to agree on a key for a symmetric cipher. The much faster symmetric cipher is then used to encrypt the conversation - the bulk of the communication. – S.L. Barth Jan 05 '18 at 13:45
  • BTW - we have a question ["How does SSL/TLS work"](https://security.stackexchange.com/q/20803/5405). You may find it interesting. I warn you, there is a LOT of information in there. You'll want some good coffee :-) – S.L. Barth Jan 05 '18 at 13:47
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    @S.L.Barth, I did go through the full thread yesterday and I must salute everyone who contributed to it. Can you post your second comment as answer? so that I can accept it. – Sreejith Nair Jan 05 '18 at 16:19
  • BTW, Which blogs/whitepapers to refer to get further insight on security related topics? – Sreejith Nair Jan 05 '18 at 16:24

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In this case, they mean the same. The messages are the data.

Symmetric ciphers are much faster than asymmetric ciphers. If asymmetric ciphers were faster, we'd simply use them for all the data exchange.

But they aren't, so instead we use the asymmetric ciphers to agree on a key for a symmetric cipher. The much faster symmetric cipher is then used to encrypt the actual conversation - the bulk of the communication.

S.L. Barth
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